Can leak detector



L. BAG LEY CAN LEAK DETECTOR Filed April 29, 19 0 Jain. 26, 1943. v

( a Sheet s-Sheet 1 BY Q ATTORNEY L. BAGL EY CAN LEAK DETECTOR Jan. 26, 1943.

Fins E 3 Sheets-Sheet 2 INVENTOR ATTORNEY Jan. 26, 1943. L; l. BAGLEY 3 CAN LEAK. DETECTOR Filed April 29', 1940 s sheets-sh s m' m' 1 E INVENTOR Hog d Bag/e51 w Patented Jan. 26, 1943 UNITED STATES" PATENT OFFICE can max ns'rsc'roa Lloyd 1. may. Hanford. Calif. Application April 29,1940, Serial No. 332,141

Claims.

This invention relates to can leak detectors and is concerned more particularly with the provision of an improved can leak detector which is especially adapted for use with filled cans of the type having a small central aperture in one end surface which is closed after filling by a soldering or tipping. operation.

In certain canning operations, for example in canning. milk, it is customary to use can filling machinery for injecting the liquid through a 'small central aperture 'in one end of the can,

while the cans are in upright position, and for thereafter closing the aperture with a drop of solder. The latter operation is commonly referred to as "tipping. In the tipping operation, the solder is often applied in a faulty manner so taken as indicated by the arrow 3 in Figure 1.

as to provide a leaky can. Also quite often sever- 01 cans go through the tipper without having any solder applied thereto during the time when the soldering flux is being renewed.

Invorder to detect and separate such leaky cans from the airtight cans, it has been customary to pass the cans after the tipping operation througha water bath to detect the presence of leaky cans by the presence of air bubbles, and said leaky cans are manually removed from the line of cans being processed. In other instances, attempts have been made to detect such leaks by passing the cans through special equipment wherein the cans are turned on their sides to be carried through the testing machine. Such operations are obviously undesirable and have certain inherent defects.

In accordance with the instant invention, an automatic can leak detector is provided wherein the cans are tested while in upright p0 ition, so that there is no possibility of spilling th contents of the cans if the aperture has not been closed, and without the .use of a water bath so that there is no danger of leakage of water into the cans.

It is a general object of the invention to provide an improved can leak detector whichoperates automatically to separate leaky from airtight cans after the filling operation.

Another object of the invention is to provide a can leak detector of the character referred to which is vacuum operated and which retains the cans in their normal upright positions and can thereby be incorporated readily in conventional can-filling machinery now in use.

Another object of the invention is to provide a 'can leak detector in which a continuous testing operation is performed with means for bypassing airtight cans past a discharge point for leaky cans.

Figure 4 is a fragmentary elevational view taken as indicated by the arrow I in Figure. 1.

Figures 5A and 53 when taken together show a developed r'.'evational view illustrating a complete operating cycle in a diagrammatic fashion.

The can leak detector of my invention can be employed with conventional filling and tipping machines such as disclosed. for example, in the patents to Dickerson Nos. 1,365,773 and 1,385,774, respectively. I l

Referring to Figure 1, a can filler of the type shown in the Dickerson Patent 1,385,773 is indi cated generally at Ill, whfle a tipper of the Dick- 'erson type is indicated at l I The tipper may include a turret wheel I! driven by gear I! from a drive shaft ll and having an endless series of peripheral pockets II for receiving the cans I! from the filler II. The gear I! rotates in a clockwise direction as viewed in Figure 1, so that the cans are carried around the periphery thereof and tipped before arriving at a discharge point where they are transferred to the can leak detector indicated generally at it.

The can leak detector ll may include a turret gear I! mounted for rotation on an upright shaft 22 suitably Journaled in a frame 23. The turret gear 2i has an upright flange 24 formed with a series of can receiving pockets 2! (Figs. 1 and 2) which are adapted to receive and hold cans in upright position with the cans resting on the upper surface of gear 2|. The frame Il may be formed in part as a ledge 26 extending around the gear. II from the tipper H to the discharge points of the cans as referred to hereinafter. If desired, a retalning'rail 21 may be suitably supported on the ledge 2h The ledge 20 and rail I! serve to prevent displacement of cans from the pockets 2| during their travel with the turret gear 2 I.

A series of vacuum lifters are carried by the. turret gear 2|, one for each pocket 24, and each lifter is mounted for vertical movement to and from engagement with a can under the control of cam means as described hereinafter.

. .To supportthe series vof lifters, there as'oassi v from the can leak detector is. at point D.

sociated with the pockets 2' a series of upright straps or brackets 3i and'fla. Brackets 3i (Fig.

2) are secured to fian'ge 24 of thegear 2i as by bolts 32. The brackets ii are connected by 4 a bracing ring 23 which carries brackets Ila. At its upper end, each bracket II and lid carries a vertically apertured guide bearing 34 suitably bolted thereon to receive a vertical arm 34 v of the associated lifter. At its upper end, each arm 20 carries a Journaled roller I! for engagement with the cam control means as referred to hereinafter, and at'its lower end carries a mounting block 88 for a vacuum lifter element 8! comprising an up ight tube 40 secured in the mounting block II as by a clamp screw 4| "ledgeztrisesgraduallyasattstothclevelof leaky cans'areremoved by means of a rotating cam disc mounted for rotation on an upright shaft-61 suitably carried on the frame and having a gear 08 meshing with turret gear 2i to be driven thereby, The disc 88 is preferably of thin construction and extends over the. gear II. To guide leaky cans onto the disc, the guide the disc 60. Associated with the disc 48 are a 'pair of guide rails H 12 for guiding the and carrying a resilient vacuum suction cup 42 at its lower end. Vacuum cup 42 is ofany suitable resilient material such as rubber and has a concave bottom face for engagementwith the end surface of a can. The upper end of tube 4| is normally closed by an air valve 48 of conventional construction having its stem projecting.

upwardly from the tube 4|. Means are provided for engaging the vacuum cup 42 of each lifterwith the can aligned therewith, the lifter being centered with respect to the associated can so that the aperture 4| thereof (Figure 2) together with its tip 41 of solder,

will be in the can surface engaged by thev cup.

Means are provided for first engaging the suction cup 42- of each lifter with the ali ned can and then for subsequently raising the lifter to."

ap ly a lifting force to the canal If a perfect seal is made, the can willbe lifted, while if a leak is present around the solder or if no solder has been applied,'the vacuum will not be main tained or will be suiliciently weak bec ause'of the air or vapor within the can, so that the can will either not be lifted or willshortly thereafter be droppedfromthelifter. V. A

As. scenin Fisure 4. the roller 21 of each lifter 4 a is adapted for engagement with a depressing cam gear" are a pair cans removed from the can leak'detector b bythe disc 88 onto a table or-track i2.-

The second of the discharge means comprises" a discharge or transfer gear ilmeshing with the gear 2i and mounted for rotation about. an Y upright axis 1.. Associated with the-transfer spectiveiy. v a

Means are provided for releasing the vacuum onairtightcansaftertheypasstheleakycan" .remover l8 and before they arrive at the dis-'" charge gear 15. This means may be in the form of a roller lLl igure 3,- iournaled in the lower end of anarm I2 pivotedat 83 onabracket l4 depending from the cam track ii. The arm 02 is urged against an adjustable stop I. by means of a tension spring 21. The height of the roller Ii is such that it will engage and depress the air'valve 43 to relieve the vacuum within the vacuum cup 42 and thereby causedropping of the cansatthepointliiasshowninligureiiust prior to the engagement of the cans with the discharge gear II. The operation of the device may be briefly described as follows: Referring to Figure 5A,

filled and tipped cans are fed to turret gear 2i at position A as indicated at Ila, immediately ahead of the depressing cam Bl. Thereafter as ll carried by an arm I2 pivoted at III on a frame bracket I4. Arm I2 is urged in a clockwise direction by spring ll against an adjustable stop screw 51 suitably mounted on the bracket 34. Spring II is of sufiicient'strength to. insure flattaping of the suction cups 42 when applied to the cans. but will yield in the event of an-obstruction to downward movement of the lifter. As seen in Figure l, cam Ii islocated to depress the lifters immediately after the can has been placed in a pocket 25, so that the first operation after a can has been received by the turret gear 2i at feed position A (Figures 1 and 5A) is a depression of the lifter arm at the position B to engage the vacuum cup 42 of the a can travels to the position indicated at lib, the associated lifter 2! is depressed by cam II to .engage the vacuum cup 42 with the top surface of-the can, after which the can travels to position C, indicated by can lie, the point of pickup by the cam track ii for operating the lifter.- I All airtight cans will be lifted clear of the tur-" ret gear 2i, while any leaky cans will not be lifted as shown at i'id, or if partially lifted will be dropped before arrival'at the point D for removal by the discharge disc II for leaky cans. Airtight cans are held in elevated position by the associated lifter Is and are by-passed over disc lifter with the top surface of the can. After engagement ofvthe' lifter with a can, a'lifting means is provided in the form of a circular cam track I for elevating the lifter and to thereby also exert a lifting force on the can with which ",the lifter is engaged. Cam track Il may be suitably supported on the frame by upright armsextending upwardly from can retaining-rail 21. The cam track It extends'from the point 0 past a leaky can removal point D, a vacuum release point I: and a discharge point P for airtight cans to the point A. The cam track ll as seen in Figures-5A and 5B gradually rises from point C to points D'and Efilld then de scends to adjacent the point B.

As seen in Figure 1, two points of discharge or removal are provided at D and l" for cans ing said lifters into engagement with the top end I surfaces of cans in said pockets before arrival at said removing means. means for operating said lifters before arrival at said removing means to 6l as shown at lie. When the can He, for ex- I ample, arrives at position E (Figure 5B), the air valve 43 is depressed byvths roller ii to relieve the vacuum which holds the can on the lifter. After such release. the can is dropped to the position shown at if! for removal by the transfer gear 1! for airtight cans.

I claim:

' 1. In a can leak detector, a can conveyingtur ret mounted for rotation about an upright axis, said turret ,having an endless series of pockets for receiving cans in upright position. means for feeding cans to said turret. means for discharging air-tight cans from said turret, means disposed intermediate said feeding means and said discharging means for removing leaky cans from said turret, a series of vacuum lifters mounted on said turret in vertical alignment with saidseries of pockets, means for successively depressof guide rails" and it, re-

of pockets, means for successively depressing said effect 1mm; of air-tight cans to by-jpass said removing means, and means for thereafter releasing cans from said lifters before arrival at said receiving cans in upright position, means for feeding cans to said turret, means for discharsing air-tight cans from said turret, means disw posed intermediatev said feeding meansand said discharging means for removing leaky cans from said turret, a series of vacuum lifters mounted on said turret in vertical alignment with said series lifters into engagement with the top .end surfaces of cans in said pockets before arrival at said removing means, and means for operating said lifters before arrival at said removing means to effect 1mm; of air-tight cans to lay-p ss said removing means.

3. In a can leak detector, a can conveying turtermediate'said feeding means, and saiddischarging means for removing leaky cans from said turret, and leak-testing means in coopera- -tive relation with each can on said turret, each leak-testing means being mounted 'for vertical movement relative to said turret and a suction cupadiacent the lower end for pressure mgagementwith the top end surface of a can whereby the'air within the cup is forced out wardly past the lip of the cup,'and a cam for engagement by each testing means during its travel with said turret to effect a depression of said testing means to force the cup into engagement with the can. 1

7.. In a can leak detector, 0. turretfor con- 4 veyong cans in upright position, means for fwd- ,ing' cans to said turret, means for'discharging air-tight cans from said turret, means'disposed intermediate said feeding means and said discharging means for removing leaky cans from said turret, and a leak-testing means in cooper- I ative relation with each canon said turret, each i said turret having 'an endless series of pockets ,1

ret mounted for rotation about anupr-ight axis, g,- leak-testing means being mounted for vertical movement relative to said turret and including for receiving cans in upright position, means for a suction cup adjacent the lower end for presfeeding cans to said turret, means for discharg ing air-tight cans from said turret, means disposed intermediate said ,feeding means and said discharging. means for removing leakycans from said turret, a series of vacuum liftersvmoimted a0 on said turret in vertical alignment with said series of pockets, means for successively depress- V ing said lifters into engagement with the top end surfaces of cans in said pocketsbefore arrival at lifters before arrival at said removing means to effect lifting of air-tight cans to by-pass said.

' removing means, and means for thereafter-releasing said cans from said lifters, saidlast,

named means comprising a vacuum relief-valve 40 tion' about an-upright axis and having an endless series of pockets for receiving cans in upright position, means interposed between said feeding means and said discharging means for removing leaky cans from said turret, and lifting means 9 including a vacuum cup mounted for downward movement into operative engagement with the top surface of said cans and responsive to a leaky condition in the can to fail to lift the can.

said lifting means being operatively engaged with said cans prior to the arrival oi'lsaid cans at said leaky can removing means.

5. In a can leak detector, means for conveying cans in upright position, means for feeding cans to said conveying means, means for discharging air-tight cans from said conveying means, means disposed intermediate said feeding means and said discharging means for removing leaky cans from said conveying means, and leak testing means forby-passing air-tight cans past said 5 removing means, said last-named means including a suction'cup for engagement with the top end surface of a can to apply a lifting force thereto and yieldable means for forcing said cup downwardly into engagement with said top end 79 surface.

6. In a can leak detector, a turret for conveying cans in upright position, mmnsfor feedin cans to said turret, means for discharging sirtight cans from said turret, means disposed insure engagement with the top end surface of a V can whereby the air between the top end surfacev of the can and the cup is forced outwardly past the lip of'the cup, a cam for engagement by each testing means during its travel with said turret to effect a depression of said testing means to force the cup into engagement with the can, and a lifting cam disposed along the path of I movement of said turret means to lift said testsaid removing means, means for operating said 33 ing means and thereby apply a lifting force through the cup-of each testing means to the can associated therewith.

8. In a can leak detector, means for conveying cans in upright position, means for feeding cans airtight cans from said conveying means, means disposed intermediate said feeding means and said discharging means for removing leaky cans from said conveying means, and leak testin v means for lay-passing airtight cans past said retherefrom, said turret" being mounted for rota- 4 moving means, said last-named means'including a suction cup for engagement with the top end surface of a can to apply a lifting force thereto, means for forcing said cup downwardly into engagement with said top end surface, and means for applying a lifting force to said suction cup while it is enga ed with the can and prior to the arrival of said can at said removing 9. In a can leak detector, a can conveying turret mounted for rotation about an upright axis,

said turret having an endless series of pockets for receiving cans in upright position, means for feeding cans to said turret, means for discharging airtight cans from said turret, means disposed. 7 intermediate said feeding means and said discharging means for removing leaky cans from said. turret, and leak testing means for by-' passing airtight cans past said removing means, 1 said last-named means including a vacuum cub carriedby said turret above said pockets for downward movement into engagement witha can positioned in the associated pocket and in engagement with said turret, means for-forcing each of said cups downwardly into engagement withthe top end surface-of a'oan while the bot- "of saidcen is resting on said turret, and means for subsequently applying a lifting force through a vacuum cup to. the associated can before the can arrives at said removing means.

10. In a ca'nleak detector, '0. can conveyin: turret mounted for rotation about an upright axis, said turret having an endless series of pockets for receiving can; in upright position.

means for feeding cans to said turret, means for discharging airtight cans from said turret,

means disposed intermediate said feeding means and said discharging means for removing-leaky cans from said turret, and leak testing means for lay-passing airtight cans past said removing means, said last-named means including a vacuum cup associated with each turret pocket for mun: airtight cans to ivy-ms said removing 'means a depressibie valve, can'ied by said cups,

-before itarrives at said discharging means to operate said valve to relieve the vacuum holding the can in encasement with the vacuum cup. I -LLOYD I BAGLEY. 

